A laser beam may be focused to a diffraction-limited spot with a high numerical-aperture objective allowing micron-sized objects in solution to be trapped in three dimensions into the region of highest light intensity. In 1970, Ashkin introduced and demonstrated the feasibility of this non-contact manipulation technique, dubbed optical or laser tweezers. Because the focused laser beam encounters an index of refraction mismatch between the particle and surrounding solution light is redirected, which induces a change in light momentum that must be balanced by the object. The net effect of this phenomenon is the immobilization of small micron-sized objects in the laser beam's focus. This tool has received broad interest because it allows non-contact, non-invasive and precise manipulation of objects in solution on the microscopic scale and has been applied in fields including chemistry, biology, colloidal, and polymer science. The utility of optical trapping in these various fields has led to interest in its implementation within microfluidic systems where, for example, direct cell manipulation would be a significant aid (e.g. lab-on-a-chip applications). However, the dynamic nature of such flowing systems, particularly those focused upon microscale separations, demand an optical trapping technique that can be spatially translated.